Thunder, hail and heavy rain are expected to batter central areas of the North Island today, following severe thunderstorms in the South Island overnight.
A front moved up from the South Island overnight and hit Wellington with rain showers this morning.
It was forecast to reach Hawke's Bay before lunchtime and continue north, bringing a high risk of thunderstorms for inland areas from central Hawke's Bay and the Ruahine Range up to Gisborne, and for eastern parts of Taupo and Bay of Plenty near the main ranges, MetService said.
While Wellington would just be hit with "big, fat drops" of rain this morning, Hawke's Bay and Gisborne could be expecting some hail, Metservice duty forecaster Liz Walsh said.
There was a chance of brief, localised flooding, but "nothing major", she said.
In the South Island, inland parts of Nelson and Marlborough could expect scattered heavy showers and a moderate risk of isolated thunderstorms this afternoon.
Last night severe thunderstorms that began in Dunedin dropped hail in Oamaru brought heavy rain, squally winds and lightning to parts of Canterbury.
Huge, dark, layered clouds glanced past Christchurch, instead heading for Banks Peninsula. Residents on the peninsula, including Little River and Akaroa, reported heavy rain, lightning and thunder.
It was the second thunderstorm to hit the region this week.
On Monday night, mid-Canterbury experienced hail stones up to 3cm in diameter that damaged crops and smashed windows in the Mayfield area.
MetService meteorologist Dan Corbett said weather in Canterbury would improve today, but another front was due over the weekend.